Bus Drivers (I2C and SPI)

Purpose

Guide agents through Linux I2C and SPI client drivers: bus registration, i2c_transfer / spi_sync, regmap abstraction, DT compatible on bus children, and probe patterns — complementing platform MMIO drivers in skills/kernel/device-drivers.

When to Use

• Sensor or PMIC on I2C/SPI bus
• Converting bare-metal SPI register reads to kernel driver
• Using regmap for multi-byte register access
• Debugging -EREMOTEIO or missing ACK

Workflow

1. I2C client driver